Year	Percent
1950	17.81214
1955	17.29031
1960	17.56163
1965	17.8377
1970	18.00351
1975	18.07448
1980	18.13691
1985	18.28211
1990	18.34813
1995	18.49368
2000	18.39761
2005	18.62933
2010	18.79419
2015	18.5032
2020	17.67216
2025	16.80262
2030	16.009
2035	15.19782
2040	14.33535
2045	13.41617
2050	12.53046
2055	11.71858
2060	10.97029
2065	10.30986
2070	9.66249
2075	9.06378
2080	8.52035
2085	8.01443
2090	7.57263
2095	7.18206
2100	6.84052